Re: [PATCH v1 net-next] net: phy: Drop #inclusion of <linux/mod_devicetable.h> from <linux/mdio.h>

[Andrew Lunn]

On Mon, Jul 06, 2026 at 11:29:19AM +0200, Uwe Kleine-König (The Capable Hub) wrote:
> <linux/mdio.h> itself doesn't use any of the device id structures. The
> files #including <linux/mdio.h> use a variety of them:
> 
> 	$ git grep -l '<linux/mdio.h>' | xargs grep --color  -E '\<(acpi_device_id|amba_id|ap_device_id|apr_device_id|auxiliary_device_id|bcma_device_id|ccw_device_id|cdx_device_id|coreboot_device_id|css_device_id|dfl_device_id|dmi_(device|system)_id|eisa_device_id|fsl_mc_device_id|hda_device_id|hid_device_id|hv_vmbus_device_id|i2c_device_id|i3c_device_id|ieee1394_device_id|input_device_id|ipack_device_id|isapnp_device_id|ishtp_device_id|mcb_device_id|mdio_device_id|mei_cl_device_id|mhi_device_id|mips_cdmm_device_id|of_device_id|parisc_device_id|pci_device_id|pci_epf_device_id|pcmcia_device_id|platform_device_id|pnp_(card_)?device_id|rio_device_id|rpmsg_device_id|sdio_device_id|sdw_device_id|serio_device_id|slim_device_id|spi_device_id|spmi_device_id|ssam_device_id|ssb_device_id|tb_service_id|tee_client_device_id|typec_device_id|ulpi_device_id|usb_device_id|vchiq_device_id|virtio_device_id|wmi_device_id|x86_(cpu|device)_id|zorro_device_id|cpu_feature)\>'
> 	...
> 
> but none of them relies on <linux/mdio.h>'s #include.
> 
> <linux/mod_devicetable.h> is a bad header mixing many different device
> id structures and thus is an unfortunate dependency because if e.g.
> struct wmi_device_id is modified all users of <linux/mdio.h> need to be
> recompiled despite none of them using struct wmi_device_id.
> 
> So drop the unused header.

While i agree that there are lots of unneeded dependencies here, does
this change actually solve anything? Pretty much every PHY driver
needs mdio_device_id, which is part of mod_devicetable.h. So it must
be getting included somehow.

I assume the long term plan is to move all the structure definitions
out of mod_devicetable.h, so a driver can include just the ones it
needs? Is this patch somehow a step along that path? Why not move
mdio_device_id into mod_devicetable_mdio.h and include that? It seems
like the more obvious fix.

	Andrew